Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full behavioral transparency burden. It discloses internal side-effecting steps ('runs hexum_check, condenses logs, scores drift') and the return shape ('next instruction or terminal status'). It does not fully explain persistence or irreversibility, but for a no-annotation tool this is substantially transparent.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences with no filler. The purpose is front-loaded, and the second sentence efficiently itemizes inputs, internal operations, and outputs. Every clause earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given six parameters, no annotations, and no output schema, the description covers the core loop-tick contract well: inputs, internal process, and return terminal states. Minor gaps remain around the exact role of notes/test_passed and whether stored logs are permanently mutated, but the description is still largely complete for an agent to invoke it correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate for parameter meaning. It adds semantics for compile_output, test_output, and files ('updated files'), but leaves loop_id, notes, and test_passed to schema names alone. This is partial compensation rather than complete.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Description opens with a specific verb and resource: 'Advance a Hexum loop one turn.' It distinguishes itself from siblings like hexum_loop_start, hexum_loop_abort, and hexum_loop_status by describing the per-turn tick behavior and possible terminal statuses.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives clear operational guidance, telling the agent to pass compile_output, test_output, and updated files, and notes that it runs hexum_check internally. However, it never explicitly states when to choose this tool instead of hexum_check or hexum_loop_start, so the usage context is implied rather than precisely scoped.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.